Renesas H8S/2318 series, Hardware Manual

Page: 380 / 1121

Rev. 5.00, 12/03, page 350 of 1088
9.4.6 PWM Modes
In PWM mode, PWM waveforms are output from the output pins. 0, 1, or toggle output can be
selected as the output level in response to compare match of each TGR.
Designating TGR compare match as the counter clearing source enables the period to be set in that
register. All channels can be designated for PWM mode independently. Synchronous operation is
also possible.
There are two PWM modes, as described below.
•
PWM mode 1
PWM output is generated from the TIOCA and TIOCC pins by pairing TGRA with TGRB and
TGRC with TGRD. The output specified by bits IOA3 to IOA0 and IOC3 to IOC0 in TIOR is
output from the TIOCA and TIOCC pins at compare matches A and C, and the output
specified by bits IOB3 to IOB0 and IOD3 to IOD0 in TIOR is output at compare matches B
and D. The initial output value is the value set in TGRA or TGRC. If the set values of paired
TGRs are identical, the output value does not change when a compare match occurs.
In PWM mode 1, a maximum 8-phase PWM output is possible.
•
PWM mode 2
PWM output is generated using one TGR as the period register and the others as duty registers.
The output specified in TIOR is performed by means of compare matches. Upon counter
clearing by a synchronization register compare match, the output value of each pin is the initial
value set in TIOR. If the set values of the period and duty registers are identical, the output
value does not change when a compare match occurs.
In PWM mode 2, a maximum 15-phase PWM output is possible by combined use with
synchronous operation.
The correspondence between PWM output pins and registers is shown in table 9-7.